For example, Type IV 'A' buildings require three-hour, fire-resistance-rated primary structural frame elements and bearing walls, but Type IV 'B' and 'C' buildings require only a two-hour fire-resistance rating
. Likewise, for Type IV 'C' buildings, exposed timber surfaces may remain entirely exposed, but for Type IV 'A' and 'B' buildings, these surfaces must be encapsulated in full or in part with fire resistant material.
Doors, door locks and frames are tested by Underwriters Laboratory and given a fire-resistance rating
. Fire-resistance ratings
indicate the amount of time the component is expected to provide protection when exposed to fire.
The perimeter joint fire barrier is classified by its fire-resistance rating
- this is the duration for which a passive fire protection system can withstand a fire-resistance test, which is typically expressed in units of time, such as 30 minutes, 60 minutes, and 90 minutes, or 0.5 hours, one hour, and 1.5 hours, ranging up to four hours.
1, I-4 Greater Than 6 Not Permitted I-3, R-2.1 Greater Than 6 Not Permitted E Greater Than 10 1 Required Fire-Resistance Rating
(Hours) Occupancy With Sprinkler System (c) H-1, H-2, H-3, L 1 H-4, H-5, L 1 Ad, B, E, F, M, S, U 0 R-1, R-2, R-3, R-3.1, R-4 1 I-2 (a), I-2.
In addition, exit doors should be at all times operational and if they are interior exit doors, should not have any damage that compromises its fire-resistance rating
. Door hardware such as closers and latching should be in working condition at all times.
Building Code include a threefold increase in the requirements for fireproofing of steel structural members along with special inspections for application of these products, an increase in the fire-resistance rating
of structural components and systems, and the addition of redundant photoluminescent exit pathway markings in buildings over 75 feet in areas already required to have emergency lighting.
What is the ideal fire-resistance rating
for buildings in the UAE?
The effect of this change is to require three-hour fire-resistance ratings
for columns, girders, and trusses (from the current two-hour rating), and an increase for shaft enclosure fire-resistance rating
from one to two hours.
Finally, the stone ballast is laid to prevent wind displacement and to provide a Class A fire-resistance rating
. When using an approved fabric, regardless of the insulation thickness, 10 lb./sq, ft.
* A reduction in the fire-resistance rating
of structural materials.
The one code change that did get added to the IBC concerned fire-resistance ratings